I have been thinking a lot about the battery bank size for my bus and would like to hear from some others on the size and configuration of your batteries. Here is some basic info on my setup. I just got an SW4024 inverter and I plan on a 12-13kw generator. I will have 3 roof airs and would like to run the front air off the inverter when under way. All heating will be from an aquahot. My cook top will be propane, I will have the usual micro-convection and my refrigerator will be household type. I will also have a fair amount of video and audio equipment. I hope this info gives a basic idea of what my battery needs will be. I would like to run my generator no more than once a day for charging. So the question is what is the best size and configuration of the battery bank?

I have a pretty similar setup, 4024, 13k wrico genset, homegrown aquahot made from a built in espar unit. I have an electric cooktop, but I rarely use it. My refrigerator is a super efficient 24 dc Sunfrost, a GE convection / microwave which I use most of the time, its really great.

My batteries are 6 AGM, 4D which give me about 600 amp hours at 24 volts. I run my genset about an hour or two a day.

What you need to do is add up everything you use lighting, refrigerator, instrurments, EVERYTHING and just do the math. A a[preadsheet is great for this, it doesn't lie. I suspect you will require a larger battery bank than mine due to your extra video and audio equipment.

A friend of mine put 800 watts of solar on his roof and has not used his generator in 9 months. He is full timing it with his wife. admittedly, his regris is not hooked up yet, he is still using an ice chest. He has 8, 8D's.

For me the solar is an ideal situation. Free once installed, and Quiet.

I bet you'll need 8 batteries, preferebly 8Ds. You may be able to get by on less, but it depends on your spreadsheet.

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Jim StewartEl Cajon, Ca. (San Diego area)

Travel is more than the seeing of sights, it is a change that goes on, deep and permanent, in the ideas of living.

I have a spreadsheet that was created by Jock Fugit (his work lives on) that I can email to you if you want one. Just email me at jim dot stewart at cox dot net and I'll send it to you. He did a nice job on it, and you really do need to know how much power you're going to use before you can intelligently choose your batteries.

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Jim StewartEl Cajon, Ca. (San Diego area)

Travel is more than the seeing of sights, it is a change that goes on, deep and permanent, in the ideas of living.

I based my battery bank on the size of my pocketbook. I could only afford eight 6 volt batteries from Sam's Club. Other true deep cycle batteries were priced 50% to 100% more expensive for the same number of amp hours. I figured twelve batteries would just be too much a chance of one going bad as I need to buy in sets of four.

With the type of camping I do, I will just start the genset if the batteries start to get low. I do have a 3,000 watt inverter and the main power draw is the 110 volt fridge.

I'll tell you of my setup that works for me. I have a complete 12v set up so the 2500 watt inverter was the biggest at the time-and truefully don't need anything bigger. I also have three roof top airs that work from the 10kw Powertech gen. Also have 2 elec water heaters, so actually might have a bigger load than you, and the 10kw has been more than enough (a bit less money than a 12-13kw). If you have a 270 amp alternator on the engine that is 24volt (28 volt actually when running) that works out to be 7560 watts available-so quite enough to run the front A/C going down the road. But, just remember that the horsepower draw to create the electricity for the front A/C has to come from somewhere-whether it be from the big alternator on the engine or the generator-either way it'll ultimately be about the same fuel burn. As far as batteries, I have two 8D Lifeline AGM's that are 255 amps each. For your setup, I'd use four 8D Lifeline AGM's that will give you 510 amp hours at 24v. Based on drawing the batteries down only to 50% discharge for longest battery life, that will give you 255 amps of realtime 24v power or a total of 6,120 watts to use. If your A/C draws a typical 1500 watts, that'll give you about 4 hours running time on the A/C alone-which in my opinion is more than enough. I've seen some buses with as many as 12 8D's that would weigh in at 1860lbs! Just remember you have to pay the fuel to haul around all this stuff. Good Luck, TomC

In my 4905 I have eight L16 batteries arranged as two parallel 24V banks of four cells each. The L16s I have are good for about 375 amp hours. Thus two 24V banks yield 750 amp hours at 24 Volts. That yields 18,000 Watt hours of power. Thus I know I can run a 100 Watt bulb for 180 hours (and more practical stuff also). The L16s make a nice compact installation.-Rick Brown in Reno